Mammalia Linnaeus 1758 [Rowe 1988], nom. cl. inval. see Class Mammalia Linnaeus, 1758
   Metatheria Huxley 1880 [O'Leary, Allard, Novacek, Meng & Gatesy 2004] see Infraclass Metatheria Huxley, 1880
     Marsupialiformes Vullo, Gheerbrant, de Muizon & Néraudeau, 2009
       [Order] †Alphadontia Archer, 1984
         [Suborder] †Hatcheriformes Case, Goin & Woodburne, 2005
           1 Family †Ectocentrocristidae [monotypic]
           2.1.1 Genus †Zeusdelphys Marshall, 1987
           2.1.2 Genus †Hatcheritherium Case, Goin & Woodburne, 2004
           2.2.1.1 Genus †Xenostylus Goin, Case, Woodburne, Vizcaino & Reguero, 1999, nom. illeg.
           2.2.1.2 †"Varalphadon" crebreforme (Cifelli, 1990)
           2.2.2 Subfamily †Chulpasiinae Sigé et al., 2009
           2.2.3.1 Genus †Mirandatherium Paula Couto, 1952
           2.2.3.2.1.1 Genus †Bobbschaefferia Paula Couto, 1970
           2.2.3.2.1.2 Genus †Wirunodon Goin & Candela, 2004
           2.2.3.2.2 Family †Caroloameghiniidae Ameghino, 1901